# 验证回文串

class Solution(object):
    def isPalindrome(self, s):
        """
        :type s: str
        :rtype: bool
        """
        str = "".join(ch.lower() for ch in s if ch.isalnum())
        return str == str[::-1]
    
s = "race a car"
a = (1,2,3,2)
print(set(a))
print(';'.join(str(i) for i in set(a)))